Drilling machine



A. 4T. DUPONT DRILLING MACHINE Snom/Lto@ F \\\r\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ -`\\\\\\\\\\\\\N\ Original Filed Feb. 13, 1928 n Y 4 NN li @N m. uw Q uw April 23, 1935.

Patented Apr. 23, 1935 UNITEDA STATES PATENT OFFICE Andrew T. Dupont, Washington, D. C.

vApplication February 13, 1928,-Serial No.V 254,035

Renewed February 11, 1933 1 30. Claims; (Cl. 1211-) Myinvention relates to drillingmachines and I3. By means ofthis construction, it will be particularly tothe means for feedingthe mecha-A seenthat the piston rod I2 and thev feed piston 9 nismand rotating the drill steel. are `prevented from either rotation or translation,

One object of my invention'is the provision of and thatV the feed cylinder and the hammer 5v improved means whereby the drill steelmay; be cylinder mounted thereon'may be fed backand rotated automatically. r forth, dependingI upon-tov which side of the Another object of my invention lie's` in an`imfeed piston 9 pressure fluid is applied. The proved construction wherein the feed piston is drill steel Il is mounted for reciprocation in the used as one of the elements for rotatingithe drill chuck Il; This: chuck carries at its forward 10, steel. end 'the spur gear I8, whichV meshes with a 10 A further object of my invention consist's'inthef gear" i9' mounted upon a stub shaft 20 upon use ofa' single motor forboth feeding the mechawhich itis free to slide. The gear I9" is driven nism to the work and rotating the drill steel. Vfrom the gear V2| mounted upon the. shaft 22 Still another object of my invention isthe'promountedfor rotation inthe front head 23 ofl the Y mi Visionzof improved means for automatically c'on-A feed'cylinder. The'portion of the shaft 22 which 15;

trollingV the feeding of the mechanismand the projects into thefeed cylinder is provided with a rotation of the drill steel. f reversible thread 2t adapted to cooperate withan Other objectsl of my invention'willbecome more internal'thread cut into'th'e piston 9' so that thel apparent in the' following' disclosure and' in the relation between the piston and the threaded part 2o accompanying drawing wherein one embodiment 24 is that of. nut and screw. For the sake of clear- 20 of my invention is clearly illustrated, nessf the threaded part 24will hereinafter be re- In the drawing: ferred to as a screw. A disk or guide 25 is pro.- Fig.l1 is a side elevation ofthe machine with vided at the extremity of the screw 241' and the parts lshown in section. space in'theV hollow piston I2.v between the disk 25 25 Fig; 2iis a partialsection of' Fig. 1 showing' the and tlfieipiston'i'is` packed with a suitable lubri- 25, automatic control valve in a position' different cant.l It will be seen thatV by this arrangement from that shown in Fig, 1'. n when pressure'uid is supplied to the feedcylin- Fig..3. is a sectionthrough: line 3-3 of Fig. 1; derzthe screw.A 24 which is secured to the` feed Fig. 4'is an end elevation of the machine viewed cylindef IIIOVeS With the latter andy iS caused to from the'right hand sideof Fig. 1.` rotate,` since the piston is held fast, and that this 30 Figs; 5 and 6 indicate sectional details'oflonecof rotation is transmitted to thedrillsteel through thev three-way valves, shown in Fig; 1.l the intermediate gears at the'front of the m'a- Fig; '7 shows a modicationchine; These gears, are securely maintained4 in Referring first to the general arrangement of position' by means ofthe plates 25 and 26",. the

parts as illustrated in Fig. 1, I is the support for outerplate'ZG serving as the outer bearing' for the 35 the machine generally adapted to be mounted on stubfshaft 2)v and they shaft 22. The plate 26 is a suitable tripod or mine column;l 2lis the hammer heldj in positioni by means of connecting rods 21 cylinder provided with'the usualhammer piston, extending between such platey and the rearhea'd or anvil 3; the drill steel 4,7having` a` passage 5 28 of the hammer cylinder. A resilient buffer 29 40 therethrough for the'passage ofa'cleansing fluid is interposed between the cross head I4 andthe 40 asis customary; andthevvalve/ chest' 5 to which rear head30of vthe feed cylinder. airY is admitted by means of the pressure: fluid Pressure fluid is admitted tothe feed cylinder pipe'l; 8 is the feed cylinder.;l 9 is theffeed piston. onleachfvside-ofthe feed piston through passages Intermediate the hammer cylinder 2 and the 30, 31 whiehreceivethe uid from apipe 32"con 4-5 feed cylinder 8 is the guide plate I0, whichguide necte'd with the main air inlet 'I. Between the 45 plate is slidingly mounted upon the guide-waysl I passages 3Il,` 3 I and the pipe 32 there is interposed provided 0n the Support l: The piston 9 of the acasing 33 which contains the automatic controI feed cylinder is provided'with a rearwardly provalve desiiggnatedgenerally at 34. The casing?` 33 iectinashank 0r piston rod I 2, Whichhas rigidly is preferably east integrally with the` hammer xed to its. rear end the rod` I3 carrying a. crossL cylinder, although itmay be mounted thereon by 50 headV it. The cross-head'is rigidly securedto the any'vsuitable means.. It is cylindrical inY general support IA by means' of al pair ofconnecting-rods appearance and is drilled to provide' a suitable I5 A pin I6 is driven through the piston rod borefor thevalve 34. I2l and the rod I3 and another piny It is driven A solid'wall 35 forms aback for the casingi 33 transversely'through'the cross-head andthe/rod and acoveriplate. is providedl at 36 so as to en'- 55 close the valve. A port is indicated at 31 into the back wall 35, the purpose of which will appear later. The pipe 32 opens into the casing 33 through two branches 38 and 39, each of which carries a rotary three-way valve indicated respectively at 40 and 4I. These valves are identical in construction and a section of one of them is shown in Figures and 6. VJhen the valve plug 42 is in the position indicated in Fig. 5, through passage is provided for the pressure fluid from the source to the valve casing 33 whereas then the plug 42 is given a quarter turn in a clockwise direction as shown in Fig. 6, admission is blocked by the plug 42 and exhaust occurs through a port 43 provided in the valve casing. Passage 35 opens into the casing 33 in the same plane as the port opening of pipe 39, While passage 3l also opens into casing 33 in the same plane as the port opening of pipe 38. The valve 34 comprises four spools or heads of which the lefthand spool has the greatest diameter, while the three remaining spools 45, 45, and 41, have the same diameter. It will be noted that the passage 35 communicates with pipe 33 through the space in the casing 33 provided between spools 46 and 41, while passage 3l communicates with pipe 33 through the space in the casing 33 provided between spools 45 and 46. It will further be noted that the space separating spools V45 and 46 isl greater than that separating spools 45 and 41. The reason for this design will appear later. Spool 41 is provided with a passage 48 extending radially to the periphery of the spool. This passage communicates with another passage 49 at right angle thereto leading to the space between the spool 41 and the back wall 35. Into the large spool 44 are mounted stud bolts 53 extending through suitable apertures 5I in the cover 3G which are of such diameter that sliding motion of the stud bolts therethrough is free.

Between the inner side of the cover 35 and the end face of spool 44 springs 52 are mounted around each stud bolt 5i) and nuts 53 are provided at the end of the bolts outside of casing 33,

v so that the tension of the springs may be adjusted and varied, and the valve 34 may be properly located in its casing with respect to the ports and passages which it controls. In addition to serving as a mounting for the springs 52 the stud bolts 50 also serve to prevent rotation of the valve 34 and to guide it in its motion of translation. A small shoulder is provided at 54 in the casing 33 so as to limit movement of valve 34 in its travel in the right-hand direction. A passage 55 is shown having a port opening into the forward end of the feed cylinder 8, while its other extremity opens into the casing 33 in the space between spools 44 and 45.

The mode of operation of my invention is as follows;

When the mainvalve (not shown) on the air inlet pipe 1 is open, pressure fluid is admitted to the valve casing 6 wherein the usual automatic Valve controls its distribution to the hammer cylinder for operating the hammerl piston. At the same time pressure fluid flows through pipes 32, 38, 39 into the valve casing 33. At this time, both valves 4i), 4I, are in the position shown in Fig. 5 and the fluid passes between spools 45, 46, into passage 3l and is admitted in the rear of the feed cylinder. The fluid also flows into the space between spools 45 and 41, passage 3B and is admitted into the forward end of the feed cylinder. Since the forward face of the feed piston 9 is larger than the rearward face thereof, the feed cylinder and the hammer cylinder carried thereon move in a forward direction. The screw 24 being carried by the feed cylinder moves therewith away from the stationary feed piston and in so doing is caused to be rotated through the nut and screw engagement between the piston 9 and the screw 24. This rotation is transmitted from gear 2l to pinion I9 and from the latter to the gear I8. This gear I8 being fast on the chuck I1 will cause the latter to rotate and also the drill steel 4 carried thereby into interlocking relation. Therefore, as long as the feeding means is operated the drill steel will be rotated. The pressure fluid admitted into the forward end of the cylinder through passage 30 will also find its way through passage 55 and into the space in the valve casing 33 comprised between spools 44 and 45. Sincespool 44 is larger in diameter than spool 45, a certain pressure will be exerted against spool 44, tending to push it towards the left in Figs. l and 2, and to overcome the pressure of springs 52. The pressure of these springs is so adjusted by means of the stud bolts 50 and nuts 53, or by the judicious selection of springs of the desired strength, that it balances the pressure of the fluid on the right-hand side of spool 44 during normal running operations so that the Valve 34 assumes the position shown in Fig. 1.

If, due to the nature of the ground, the drill steel should become stuck, rotation of gears I8,

VI9 and 2 I, will be interrupted and these gears will lock. rIhe rotation ofscrew 24 which through the shaft 22.is keyed to gear 2I, will also stop. As soon as this occurs the fluid admitted into the forward end of the feed cylinder will be unable to continue theforward feed since the feed cylinder will be locked to the feed piston through nut and screw engagement between the feed piston 9 and the screw 24. Therefore, the pressure in the forward end of theV feed cylinder will increase and this pressure rise will be transmitted through passage 55 into the space between spools 44 and A45 ofthe valve 34, where, acting against spool 44, it will overcome the pressure of springs 52 causing the valve 34 to shift to the position indicated in Fig. 2.

When the valve 34 is in this position, the spool 41 thereof closes port opening of pipe 39, so that fluid admission to passage 35 and the forward end of the feed cylinder ceases. At the same time passage 48 in 'spool'41 coincides with the port opening of passage 30 and exhaust occurs from the forward end of the feed cylinder, through passages 3D, 48,l 4S and through the port 31 in the wall 35 into the atmosphere. The space between the spools 45 and 46 is such that when the Valve 34 is in the extreme left-hand position shown in Figure 2, admission of pressure fluid from pipe 38 to passage 3l and the rear end of the cylinder is continued. Therefore, as soon as the pressure in the rear end of the feed cylinder overcomes that in the front end thereof, the tendency is for the feed to be reversed and the screw 24 to be rotated in the opposite direction. This will cause the drill steel to be rotated in the opposite direction and to free itself from the seam. During this period of feed retraction and reversal of rotation, the valve 34 will be maintained in the position shown in Figure 2, not only by the pressure fluid against spool 44 but also by the exhaust pressure of the iiuid against Vthe end spool 41, which helps to delay the return of the valve. As soon, however, as these pressures, as well as the pressure in the forward end of the cylinder, have fallen toa considerable extent, the springs 52 vIl() willshiftf the valve 34" back to its-'normalposition shown in-ligureV l, and forwardfeedrand normal drill steel rotation will be resumed. vShould the steel againbecome stuck when it reaches its outermostposition, the conditions described-above will' again obtain, that is, the feed and rotation will be reversed and then returned to normal. This will occurseveral times until the obstruction is completelycleared. It may be desirablejatl times to prevent rotation ofthe steel, suchfor instance, as' whenA spotting the hole or when retracting the feed. This may be' accomplished by sliding the pinion I9Fon shaft 20. For this purpose pinion I9- is providedwith an extension 55.in which a groove Y56 is' provided. A fork 51 straddles this groove and is providedv with a suitableI handle (not shown)` extending through casing 26 for manipulation. If desired,a speed` gear shift of thev type shown in'United States patent to Kimman No; 639,737 ofv 1899, may be used, so that the drill steel may be rotated at diiferentspeeds. It will be understood, `of course, that the'pitch of thread on'serew 24 aswell as the sizes of' gears i8, i9 and 2|, will be judiciously chosen so that the 'f eihciency of the combined feeding and rotating means will be as high as possible.A

When the tool has been driven to thev work as Yfar as the'length ofthe drill will permit or when the feed cylinder and the hammer cylinder will be retracted. When it is desired to exhaust both the forward and rearward ends of the feed cylinder, both valves 49 and 4l', are turned tothe exhaust' position shown in Fig. 6.

vIn order to maintain valve 34 in the position shown in Fig. 2, for some time after the pressure inthe forward feed cylinder end has fallen below thatM in the rearward feed cylinderend, a dashpot system such as shown in Fig. 7, may be used. In this figure valve' casing y3.3 is provided with an'additionalchamber 58', containing oil'or other suitableliquid. A piston 59 having arestricted port 'therethrough is adapted to travelv in this chamber and is connected by means of a stem ii! with the valve 34. A wall 62 separates chamber f 58 from the chamber in which valve 34 is located; When, theA rotation of the drill steel is prevented, the valve 34 is moved from the posi- Y tion shown in Figure v1 to that shown in Fig. 2, asV explained above, causing exhaust of the forward cylinder end and of the space between spools44 and 45. Due to the dash-pot arrangement, itl will take some time forl the valve 34 to resume' its normal position and during this time the pressure fluid in the rear feed cylinder end will'reverse the direction of feeding motion and the rotation of the drill steel. Delay of the return of valve 34 to its normal position is also increased, as in Figures 1 and 2, due to thepressure of: the exhaust fluid acting' against the end spool 41. u The return of valve 34- to normal position maybev differently timed depending on the size of port 6G and means well known in the dash-pot artmay be usedvto vary the size of the leak port at will. v u

The advantages of my invention will be readily apparent t'o' one skilled in the art to which it appertains. Heretofore, two separate motorshove been used, one to Vrotate the tooland another and separate motor'for feeding it tothe work; Where my invention is used, a single motor performs both operations. Furthermore, in embodying my automatic controlv valve in a drilling machine, men whoshave heretofore had to manually` release the stuck drills with all the delay incident thereto, may be free to perform otherwork. A single workman may supervise a= Whole'battery of the machines'equipped with my invention.

Y While I have lin'this application specifically described'two formsiwlfiiehl my invention may vassume inpractice, it will be understood that these forms-of the same `are shown for purposes of villustration and' that the invention mayv be modied andy embodied in other formswithout departing from its spirit or the scope ofthe appendedv claims. Y

'What I'y claim is:

l. Inl aV drilling machine, a hammer cylinder, a pneumatic hammer'therein, a-drill steel operated by said pneumatic hammer, feeding means for said steel comprising a feed cylinder, astationary hollow feedpiston therein, al memberf in said pistonV having therewithv a nut and screw connection, connecting means between said member andfsaid' drill steel including a clutch andmeans foradmitting pressure fluid to the feed cylinder whereby feeding. and rotatingv the steel occurs simultaneously, or' feeding occurs independently, at the willv of the operator.

2. 'In a drilling machine, ahammer motor,-a motor for feeding said hammer motorcomprising two relatively movable elements, a memberl conrie-cted to one of said elements and? having a nut and screw'engagement with the other of said elementsso that upon relative motionv between said elements the member is rotated and means for 'connecting and disconnecting at will the member with the drill steel" tov rotate'the latter when the member rotates, said last namedmeans beingindependent of the hammer motor.

3. In a drilling machine having a drill steel therein, meansfor feeding and rotating the steel in one direction, and means responsive to resistance to rotation forV automatically reversing the direction of feed and of rotation.

4. In a drilling maohina'a hammer motor, a

drill steel operated thereby, a single motor for feeding and rotating said drillV steel and means responsive to resistance torotation for revers'- ing said motor. f

5. Ina drilling machine, a hammer motor, a drill steel operated thereby, a single motorr for feeding androtating said drill's'teel andmeans responsive to pressure conditions in said single motor caused bysticking of the drill steel for reversing the latter.

6. In a drilling.v machine, av hammer motor, a

side of said piston and means responsive to pressure conditions on one side of said piston for interrupting admission of pressure fluid tothe said'side Aof the piston;

8. In a'drilling machine, a hammer motor, a drill steel operatedthereby, a motor-for feeding and rotating the'r drill steel comprisingla cylinder and a piston, means for simultaneously admitting pressure fluid on each side of said piston and means responsive to resistance to rotation for interrupting admission of pressure fluid to one side of said piston and exhausting the pressure fluid therefrom.

9. In a drilling machine, a hammer motor, means for feeding said hammer motor to the work comprising a cylinder and a piston, means for simultaneously admitting pressure fluid on each side of said piston and means responsive to pressure conditions on one side of said piston for interrupting` admission of pressure fluid to the said side ofthe piston and exhausting it therefrom.

10. In a drilling machine a hammer motor, a drill steel operated thereby, a single motor for feeding and rotating said drill steel, and means responsive to resistance to rotation for controlling the direction of movement of said single motor.

l1. In a drilling machine having a drill steel therein, means for feeding and rotating the steel in one direction and means responsive to resistance to rotation for automatically reversing the direction of feed and rotation and thereafter resuming feed and rotation in the first direction.

l2. In a rock drill of the hammer type, the combination of a single actuating means for feeding and rotating the drill steel, and means responsive to the resistance to rotation for automatically controlling said single feeding and rotating means. f

`13. In a drilling apparatus, a tool, a tool actuating motor, a motor for rotating said tool and feeding said tool actuating motor, and means comprising a valve responsive to variations of pressure within said'second named motor for varying its operation.

14. In a drilling mechanism, work performing means comprising a percussive motor, a tool actuated thereby, a reversible motor for rotating said tool and feeding said percussive motor, and pressure fluid operated means responsive to work conditions for reversing said second mentioned motor.

l5. In a drilling mechanism, a percussive motor, a tool operated thereby, a fluid pressure motor for rotating said tool and feeding said percussive motor, and pressure fluid operating means responsive to pressure changes in said second mentioned motor for reversing the direction of its movement.

16. In a drilling mechanism, a percussive motor, a tool actuated thereby, a fluid pressure motor for rotating said tool and feeding said percussive motor, and means having communication with said rotating and feeding motor, and automatically controlled by pressure changes in saidA motor for regulating the direction of the movement of said motor.

1'7. In a drilling mechanism, a hammer motor, a drill steel actuated thereby, a combined rotation and feeding means for effecting positive feed and rotation of the drill steel in either direction, and means responsive to drill steel rotation for automatically reversing said rotation and feeding means.

i8. In a drilling apparatus, a percussive motor, a tool actuated thereby, a motor for rotating said tool and feeding said percussive motor, and means to control the operation of said feeding and rotating motor, whereby retraction from the work and reversal of rotation occur upon encountering abnormal work conditions.

19. In a drilling machine, a percussive motor, a drill steel operated thereby, a single motor for feeding and rotating said drill steel, means responsive to resistance to rotation for controlling the direction of movement of said single motor, and means permitting feeding without rotation of the steel.

20. In a drilling machine, a drilling tool, a drilling motor, a motor for feeding said drilling motor comprising a cylinder and a piston therein, a member having a screw arrangement with said piston whereby said member rotates upon relative movement between said cylinder and piston, and gearing connections between said member and said tool whereby said feeding motor causes rotation of the drilling tool.

21. In a drilling machine, a drilling tool, a drilling motor, a motor for feeding said drilling motor comprising a cylinder and a piston therein, a member having a screw engagement with said piston whereby said member rotates upon relative movement between said cylinder and piston, and gearing connections between said member and said tool including a clutch.

22. In a drilling machine, a drilling tool, a drilling motor, a motor for feeding said drilling motor comprising a cylinder and a piston therein, a member having reversiblescrew engagement with said piston whereby said member rotates in either direction upon relative movement in either direction between said cylinder and piston, connecting means between said drilling tool and said member, whereby the tool is rotatable with said member, and means responsive to resistance to rotation for controlling the operation of said feeding motor. i Y

23. A machine for drilling holes having a frame, a tool carried thereby, means for rotating the tool and for feeding it to the work, said means including .a `cylinder and a hollow piston, a portion of the rotating means extending through said hollow piston, and means to alternate the direction of the tool feed when resistance to the tool is encountered.

24. A drilling machine including a drilling tool, means for feeding saidtool, additional means for rotating said tool including a connection with said feeding means and extending therethrough, and automatic means for retracting the tool from the work when resistance is met by said tool during its operation.

25. A drilling machine including a drilling tool, means for feeding said tool to the work, additional means for rotating said tool including a connection with said feeding means and extending therethrough, and means for retracting the tool from the work when resistance is met .by said tool during its operation and for resuming normal feed when the resistance has subsided.

26. A machine for drilling holes having a frame, a tool carrier thereby, fluid pressure means for rotatingV the tool and for feeding it to the work, said means including a cylinder and a hollow piston, a portion of the rotating means extending through said hollow piston, and fluid pressure means for reversing the direction of the tool feed when resistance to the rotation of the tool is encountered.

27. A drilling machine including a drilling tool, uid pressure means for feeding said tool, additional means for rotating said tool including a connection with saidA feeding means and extending therethrough, and automatic pressure means for retracting the tool from the work when resistance is metl by said tool duringitsV means for rotating said drill including an element extending through said hollow piston and having engagement therewith, and means for reversing the feeding direction controlled by the drill resistance to the work.

30. In a drilling machine, a drill carried thereby, fluid pressure means forffeeding said tool to the work including a cylinder and a hollow piston therein, means for rotating said drill including an element extending through said hollow piston and having engagement therewith, and fluid pressure means for reversing the feeding direction controlled by the drill resistance to the work.

ANDREW T. DUPONT. 

